Do I have good title to this copy of XP?

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From: Samm (noone_at_no-where.com)
Date: 03/14/04 

Date: Sun, 14 Mar 2004 22:22:59 GMT

If a private individual sells me a machine with XP on it then do I
have good title to use that copy of XP?

The giver says he has lost the CD and manuals and that he has gone
over to using Mac. I tend to believe him.

I figure I can extract the XP key using one of the tools avilable
to do this.

But will it be legitimate ?